let/bar
let/baz="baz"

id/alwaysFoo="foo"
id/sometimesBar=bar
id/sometimesBaz=baz

button onClick() {
  bar = bar ? null : "bar"
  baz = baz ? null : "baz"
} -- toggle


div id=alwaysFoo -- foo
div id=sometimesBar -- bar
div id=sometimesBaz -- baz